Method of translating a voice signal to a series of discrete tones

A method for generating an identification signal, comprising:

• accepting as input a voice signal of limited duration;
• translating said voice signal to a representation of a series of discrete tones, including generating a digital representation of said voice signal, dividing said digitized signal into a plurality of frames, extracting analysis data from each said frame, formatting said analysis data into a frame representation, and grouping said frames into a plurality of regions;
• producing a control signal from said representation of discrete tones, said control signal suitable for causing a transponder to generate a signal, where said generated signal is human-recognizable as a translation of said voice signal;
• determining the existence of a candidate note start frame in each said region;
• determining a stop frame corresponding to each start frame;
• forming an initial set of fundamental frequencies from said start and corresponding stop frames;
• removing from said initial set those fundamental frequencies having corresponding time-domain energies less than an energy threshold to form a modified set of fundamental frequencies;
• removing from said modified set those fundamental frequencies having corresponding voicing probabilities less than a voicing probability threshold to form a twice modified set of fundamental frequencies;
• determining a median for each member of said twice modified set;
• determining a mode for each member of said twice modified set;
• determining a distributional type for each member of said twice modified set with an associated class confidence estimate;
• and
• assigning a MIDI note number to each member of said twice modified set in response to said mode, said median, said distributional type and said class confidence estimate, whereby a note sequence is created.